Waste acid treatment system and method

Abstract

The invention provides a waste acid treatment system and method, and belongs to the technical field of water treatment. The system includes a waste acid adjusting pool, a waste acid lifting pump, a first neutralization tank, a secondary neutralization tank, a thickener, a first pressure filter feed pump, a first-stage pressure filter, a slurrying tank, a second pressure filter feed pump and a secondary-stage pressure filter which are connected in turn, and the thickener, the first-stage pressure filter, and the secondary-stage pressure filter are respectively connected with a normal acid wastewater regulation tank. The system uses limestone powder slurry or lead oxide slurry prepared from limestone or lead oxide dust for waste acid treatment, the cost of (300-70) * 200 * 12 = 552000 yuan can be save each year according to the monthly lime use amount of 200t, the lime price of 300 yuan / t, the limestone price of 70 yuan / t, slurrying washed gypsum residue is smooth in appearance, water soluble arsenic and other harmful impurities can be washed away, the quality is better, and the washed gypsum residue is more conducive to the comprehensive utilization.

Description

[0001] technical field [0002] The invention relates to a sewage acid treatment system and method produced by metal smelting, belonging to the technical field of water treatment. Background technique [0003] Sulfuric acid will be produced in the sulfuric acid section of the lead-zinc smelter. The sulfuric acid concentration is about 6-9g / L, and it also contains a certain amount of As, F, Cl, Cd, Zn and other components. The traditional process generally uses quicklime for neutralization, and the generated waste residue is sent to the slag yard for stockpiling or a small amount of takeaway after pressure filtration and dehydration, and the filtrate is sent to the ordinary acid wastewater treatment system for treatment, which will bring the following disadvantages: [0004] 1. The acidity of sewage acid treatment is relatively high, and quicklime is generally used for treatment, which requires a large amount of quicklime, which requires a large amount and high cost; [0005...

AI Technical Summary

Problems solved by technology

[0004] 1. The acidity of sewage acid treatment is relatively high, and quicklime is generally used for treatment, which requires a large amount of quicklime, which requires a large amount and high cost;

[0005] 2. The gypsum slag produced by the sewage acid treatment system is not good in shape, has many impurities, and has a large content of crystal water, making it difficult to dehydrate the slag

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